<p>Caro´s acid, a mixture of peroxymonosulphuric acid (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(HS{O}_{5}^{-}\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>H</mi> <mi>S</mi> <msubsup> <mi>O</mi> <mrow> <mn>5</mn> </mrow> <mo>-</mo> </msubsup> </mrow> </math></EquationSource> </InlineEquation>), hydrogen peroxide (<InlineEquation ID="IEq2"> <EquationSource Format="TEX">\({H}_{2}{O}_{2}\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>H</mi> <mn>2</mn> </msub> <msub> <mi>O</mi> <mn>2</mn> </msub> </mrow> </math></EquationSource> </InlineEquation>) and sulphuric acid (<InlineEquation ID="IEq3"> <EquationSource Format="TEX">\({H}_{2}S{O}_{4}\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>H</mi> <mn>2</mn> </msub> <mi>S</mi> <msub> <mi>O</mi> <mn>4</mn> </msub> </mrow> </math></EquationSource> </InlineEquation>), is a powerful oxidizing agent in acidic solution, even at room temperature. This work presents a basic study on the thermodynamics and kinetics of the use of Caro´s acid in some hydrometallurgical processes. Prepared by the reaction between H₂O₂ and H₂SO₄, Caro´s acid oxidizes very fast Mn(II) to Mn(IV) to form high-purity MnO₂, providing a method to remove Mn²⁺ from aqueous solution. It also gives an alternative to leach ores refractory to conventional cyanidation, allowing the recovery of the gold contained in a calaverite ore (AuTe₂) and the silver contained in a highly refractory compound as synthetic hessite (Ag₂Te), which is completely dissolved with a concentration of 5% (v/v) of H₂SO₅ in Caro’s acid.</p> Graphical abstract <p></p>